Because the weather was nice, Ms. Lee, a woman in her 30s who works at an office, started outdoor running. Not long after, she developed a pinkish spot about the size of a finger on her abdomen. She initially thought it was just skin stretching and didn't pay much attention. Soon, two or three more red spots appeared and spread to her sides and thighs. The affected area became itchy, and the skin started to peel off, so Ms. Lee visited a dermatologist and was diagnosed with 'Rose Bacterial Cellulitis.'

Pityriasis rosea is an acute skin inflammatory disease, also known as the "cold of the skin." It commonly occurs during seasonal changes when immunity is weakened, and sometimes symptoms such as headache, fatigue, and fever appear before the skin rash.

Skin rashes initially appear as pink oval spots on the central part of the body, then spread outward in a diagonal downward pattern resembling a Christmas tree. Usually, the spots are surrounded by thin, white scales. Occasionally, the rash can spread to the limbs, but it rarely occurs on the neck or face. Three out of four patients experience itching. It commonly occurs in individuals aged 15 to 40, with a higher prevalence among women.

Although the exact cause has not been identified, the most plausible hypothesis is that herpesvirus types 6 and 7 become active when immunity declines, leading to roseola. It is not contagious.

Most rashes disappear spontaneously within 6 to 8 weeks after appearance, and if symptoms are not significantly uncomfortable, no special treatment is necessary. However, if itching or excessive rash accompanies it, antihistamines and topical steroid creams can be used to alleviate symptoms. Phototherapy may also be performed.

If 6 to 8 weeks have passed and the spots do not disappear and persist for several months, it is advisable to see a dermatologist for an accurate diagnosis. This is because there are various skin conditions that can be confused with each other, such as secondary syphilis, coin-shaped eczema, seborrheic dermatitis, droplet psoriasis, ringworm, and viral rashes.